A multidisciplinary group has been assembled to make a concerted effort to increase our knowledge of reproductive physiology and reproductive biochemistry. The disciplines now represented comprise: clinical investigation, endocrinology, neuroendocrinology, neurosurgery, immunocytochemistry, immunochemistry, endocrine biochemistry, cytogenetics, gametogenesis and bioengineering. Specific objectives for the immediate future are the understandin of: - the biosynthesis and metabolism of the gonadal and adrenal hormones, the neuroendocrine control of gonadotropin and prolactin secretion in primates, the application of control theory to problems of reproduction, the relationship between fertility, biochemical aspects of sperm function and genetic or acquired defects in human spermatogenesis.